The answer to 'why is my surge protector power surge' is that your surge protector may have been overloaded or damaged, causing it to fail and no longer protect your electronics. Common causes include power surges from the electrical grid, lightning strikes, or plugging in too many high-wattage devices. Symptoms include the surge protector's indicator light turning off, buzzing or clicking noises, or your devices not receiving power.
If your surge protector has failed, you'll need to replace it. Surge protectors have a limited lifespan and can wear out over time, especially if they've had to absorb multiple power surges. When shopping for a new one, look for a model with a high joule rating and a long warranty. Be sure to unplug all your devices before swapping out the surge protector.